In the coffee world, a tamper is used to compress grounds into an espresso machine's portafilter. This helps to create required pressure to allow more of the oils from the ground coffee to enter the cup, providing the intense flavor of espresso.
The preparation of espresso coffee involves running hot water through a compressed portion of coffee grounds in order to deliver a desired serving of concentrated espresso coffee.
It is well known in the art, the amount of compression of the coffee cake influences the quality of the beverage produced thereby.
The compression of the coffee grounds in the basket of the portafilter is known as tamping, and may be performed using a variety of tampers.
Types of espresso tampers known in the art include handheld manual tampers, fixed tamping surface typically mounted on coffee grinding machines, and large tamping machines which typically exert tamping forces by means of a lever actuated or mechanized plunger.
These tampers are generally solid ornamental objects configured with a lower surface adapted to allow the application of pressure on the coffee grounds in the filter basket, and an upper portion suitable for holding in the hand of the user. Following compression of the grounds, the handheld tamper is typically spun on the surface of the compressed grounds in order to form a smooth polished surface.
Large amount of loose grounded coffee has to be added to the portafilter so that after tamping, the portafilter is filled with compressed grounds. The amount of coffee grounds is determined by the tactile judgment of the user of the tamping device. It is therefore very difficult for even a skilled user to obtain precise amount of ground coffee using a conventional manual tamper. User tends to over fill the portafilter with coffee grounds. When tamping with a conventional tamper, loose grounds will fall off the portafilter causing quite a mess, this is particular the case for the less skillful.
Also, some coffee grounds adhere to the base of the tamper and wasted when the compression is completed with the tamper being removed. The amount of wasted grounds becomes more significant upon repeated application.